Neutral and Cationic Tridentate Bis(N-heterocyclic carbene) Ether Ruthenium Alkylidene Complexes in Metathesis
Bibliographic record
Abstract
The ligand precursors (MeOCH 2 CH 2 ImCH 2 CH 2 ImMe]X 2 (X = Cl ( 2a ), Br ( 2b )) were prepared from reaction of methoxyethylimidazole with a haloethylmethylimidazolium halide. Subsequent conversion to Ag 2 X 2 (MeOCH 2 CH 2 ImCH 2 CH 2 ImMe) (X = Cl ( 3a ), Br ( 3b )) was achieved by treatment with Ag 2 O. Reaction of 3a or 3b with RuCl 2 (PPh 3 ) 3 ( 4 ) afforded RuCl 2 (PPh 3 )(MeOCH 2 CH 2 ImCH 2 CH 2 ImMe) ( 5 ). In a similar fashion treatment of 3a or 3b with RuCl 2 (═CHPh)(PCy 3 ) 2 gave the alkylidene complex RuCl 2 (═CHPh)(MeOCH 2 CH 2 ImCH 2 CH 2 ImMe) ( 6 ). In several standard metathesis tests 6 was shown to be a poor catalyst. The related ligand precursor [O(CH 2 CH 2 ImMe) 2 ][Br] 2 ( 7 ) was prepared, transformed to (AgBr) 2 [O(CH 2 CH 2 ImMe) 2 ] ( 8 ) and reacted with RuCl 2 (═CHPh)(PCy 3 ) 2 to give RuCl 2 (═CHPh)[O(CH 2 CH 2 ImMe) 2 ] ( 9 ). Reaction of 9 with B(C 6 F 5 ) 3 generated the cationic species 10, which was shown to be the dimer [RuCl(═CHPh)(O(CH 2 CH 2 ImMe) 2 )] 2 [ClB(C 6 F 5 ) 3 ] 2 in the solid state. Compound 9 was also ineffective as a metathesis catalyst; however, 10 proved to be a moderately active metathesis catalyst at 45 and 80 °C in RCM, ROMP, and CM test reactions. Structural data for 3a, 5, 6, 9, and 10 are reported, and the implications of this work in catalyst development are considered.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".